I don't know but i don't use autofill can't depend on it .First thing i do when i register at a site is write down on papper each time .Then i put it all on a cd or external hard dive and you will always have them then just update it as you get more sites.It is very easy to write it down on papper as long as u do it when registering.

I didn't see any option to import usernames and passwords in chrome and firefox browser. Is there any extension can do it?If other browsers can not import the data, it's useless to export the autofills from avant browser.